The present invention relates to semiconductor device fabrication and integrated circuits and, more specifically, to structures including passive device structures and methods for fabricating passive devices.
Diodes, capacitors, and resistors are passive devices in an integrated circuit that are incapable of switching electric currents. A diode, for example, may include two adjacent doped regions in a semiconductor wafer, in which the two doped regions have opposite conductivity types, to define a p-n junction.
In integrated circuit structures that include fin-type field-effect transistor (FinFET) devices, a passive device such as a diode may also include a plurality of fins that contact a conductive contact. Fins may be electrically isolated by an isolation dielectric material, but during fabrication some portion of the isolation material may be etched, and if the etching process is not well controlled some portions of the isolation material may be etched too deeply. When the conductive contact is formed it can penetrate into these deeply etched areas of the isolation material, degrading electrical isolation and causing current leakage in the device. As integrated circuit devices have continued to shrink, ensuring that current leakage and electrical short circuits are prevented has become an increasingly important consideration in fabrication processes.